USS Pennsylvania: The Evolution of Submarine Technology

The USS Pennsylvania, an Ohio-class submarine, is the largest submarine in the US Navy, with the capability to dive to over 250 meters and stay submerged for six months. Its existence is the result of over 200 years of engineering evolution, with six key stages in submarine technology development.

Early Submarines

The story of the USS Pennsylvania begins with the world’s first war submarine, the “Turtle”, a hollow wooden sphere built in 1776 during the American War of Independence. The Turtle had significant limitations, including a tiny window and a quickly depleting air supply. An experiment was conducted to simulate the conditions inside the Turtle, highlighting the major limitation of the submarine.

Modern Submarines

In contrast, modern submarines like the USS Pennsylvania can stay submerged for months by using a process that splits seawater into hydrogen and oxygen, providing a sustainable air supply for the crew. The process of electrolysis is used to extract oxygen from water, which can be demonstrated by relighting a glowing splint with the extracted gas.

History of Submarines

The history of submarines is also explored, from the early 13-meter long H.L. Hunley to the development of underwater weapons like the spar torpedo. The challenge of controlling the depth of a submarine is demonstrated, and it is noted that early submariners looked to nature for inspiration, such as copying the fins of a fish to create metal fins on the side of the submarine.

Development of Torpedo Technology

The development of torpedo technology has significantly evolved over time, from the early 7-meter long torpedoes that required enormous batteries to the modern guided torpedoes used by submarines like the USS Pennsylvania. The Pennsylvania’s Mark 48 torpedoes can be guided onto their target and are not limited to firing in a straight line, allowing for more precise and effective attacks.

Nuclear-Powered Submarines

The development of nuclear-powered submarines revolutionized underwater warfare, starting with the launch of the USS Nautilus in 1954, the world’s first nuclear-powered submarine. This innovation allowed submarines to travel vast distances without needing to refuel at sea, with the Nautilus able to cover 100,000 kilometers on just four kilograms of uranium fuel.

Launch of Missiles from Submarines

The concept of launching missiles from submarines was first explored by the Russians, but their design required the submarine to surface, making it an easy target. The Americans aimed to improve upon this by designing a submarine that could launch missiles while remaining underwater. The USS George Washington, which carried 16 Polaris missiles, effectively prevented warfare by being so destructive and frightening that the concept of warfare between nations who owned them became unthinkable.

USS Pennsylvania’s Capabilities

The USS Pennsylvania, a nuclear submarine, is on constant readiness to launch its 24 Trident nuclear missiles in response to a direct order from the President. The crew runs through a well-rehearsed exercise to launch a nuclear strike, with the command to launch encoded with a cipher to ensure authenticity. The submarine uses a unique system to launch its missiles, propelling them through the water into the air using a column of steam.

Silence and Stealth

To remain undetected, the submarine must be silent, with everything on board insulated to minimize noise caused by vibrations, and its propeller designed to reduce the noise caused by bubbles and steam. The crew’s primary mission is to remain at sea undetected, making silence a crucial aspect of their daily operations.

Term	Definition	Example Usage
Electrolysis	A chemical process that uses an electric current to split a molecule into its component parts, often used to extract oxygen from water.	The USS Pennsylvania uses electrolysis to extract oxygen from seawater, providing a sustainable air supply for the crew.
Torpedo	A self-propelled underwater missile used in naval warfare, often launched from a submarine.	The USS Pennsylvania is equipped with Mark 48 torpedoes, which can be guided onto their target and are not limited to firing in a straight line.
Nuclear-Powered	Describing a vessel or system that uses nuclear energy as its primary source of power.	The USS Nautilus was the world’s first nuclear-powered submarine, allowing it to travel vast distances without needing to refuel at sea.
Ballistic Missile	A type of missile that follows a ballistic trajectory, often used for long-range attacks.	The USS Pennsylvania is equipped with 24 Trident nuclear missiles, which can be launched in response to a direct order from the President.
Stealth Technology	Design and materials used to reduce the visibility or detectability of a vessel or aircraft.	The USS Pennsylvania uses stealth technology to remain undetected, with everything on board insulated to minimize noise caused by vibrations.
Submarine	A watercraft capable of operating underwater, often used for military or research purposes.	The USS Pennsylvania is a nuclear submarine, capable of diving to over 250 meters and staying submerged for six months.
Guided Missile	A type of missile that can be controlled or guided during its flight, often used for precision attacks.	The USS Pennsylvania’s Mark 48 torpedoes are guided missiles, which can be controlled during their flight to ensure a precise hit.
Propulsion System	A system used to generate power and propel a vessel through the water.	The USS Pennsylvania uses a unique propulsion system to launch its missiles, propelling them through the water into the air using a column of steam.
Cipher	A code or encryption system used to secure communication or data.	The command to launch a nuclear strike from the USS Pennsylvania is encoded with a cipher to ensure authenticity.
Sonar	A system used to detect and navigate underwater using sound waves.	Submarines like the USS Pennsylvania use sonar to detect and track targets, as well as to navigate through the water.

USS Pennsylvania Vocabulary Quiz

Test your knowledge of the USS Pennsylvania and submarine technology with this 5-question multiple-choice quiz.

Question 1: What is the process used to extract oxygen from water in modern submarines like the USS Pennsylvania?

A) Respiration B) Electrolysis C) Photosynthesis D) Decomposition

Question 2: What is the name of the first war submarine, a hollow wooden sphere built in 1776?

A) USS Pennsylvania B) H.L. Hunley C) Turtle D) Nautilus

Question 3: What type of torpedoes are used by the USS Pennsylvania, which can be guided onto their target?

A) Spar Torpedoes B) Mark 48 Torpedoes C) Polaris Missiles D) Trident Missiles

Question 4: What is the primary mission of the crew of the USS Pennsylvania?

A) To launch nuclear missiles B) To remain at sea undetected C) To travel vast distances D) To conduct experiments

Question 5: What is the system used by the USS Pennsylvania to launch its missiles, propelling them through the water into the air?

A) A column of steam B) A system of pulleys C) A hydraulic pump D) A magnetic field

Answer Key:

1. B) Electrolysis 2. C) Turtle 3. B) Mark 48 Torpedoes 4. B) To remain at sea undetected 5. A) A column of steam

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Passive Voice and Subjunctive Mood in Technical Descriptions

The passive voice is often used in technical descriptions to emphasize the process or action rather than the doer. For example, “the USS Pennsylvania can be guided onto its target” emphasizes the capability of the submarine. The subjunctive mood is used to express necessity, possibility, or doubt, as seen in “it is necessary that the submarine remain undetected.” The use of these grammatical structures allows for clear and concise communication of complex technical information.

Quiz Time!

Choose the correct answer for each question:

1. The USS Pennsylvania ___________ to dive to over 250 meters and stay submerged for six months. A) is capable B) has been designed C) can be modified D) was built
2. The process of electrolysis ___________ to extract oxygen from water. A) is used B) can be used C) has been used D) must be used
3. The development of nuclear-powered submarines ___________ to revolutionize underwater warfare. A) was necessary B) has been necessary C) is necessary D) would be necessary
4. The crew of the USS Pennsylvania ___________ to run through a well-rehearsed exercise to launch a nuclear strike. A) is required B) has been required C) can be required D) may be required
5. The submarine ___________ to be silent to remain undetected. A) must be B) can be C) has been D) will be

Answer Key:

1. B) has been designed
2. A) is used
3. A) was necessary
4. A) is required
5. A) must be